Rotary drill-bit.



W. KAMMERER.

ROTARY DRILL-BIT.

APPLICATION FILED AUG. 31, 1910. RENEWED APB..10, 191s.

1,66 4 0 Patented June 3, 1913.

l/l/i/Zesses //7 yen/5f WILLIAM KAMMERER. o'nnos Antennas, mum.

ROTARY DRILL-sir.

Specification of Letters Patent,

Patented June a, rare.

Application filed August 31, in -ser al No. 579,947: Renewed April 10,1913. Serial No. 760,317.

To all whom it may concerns" Be it known that I, WILLIAM KAMMERER,

a citizen of the United States'of America," residing at Los Angeles, in the county of Los Angeles, State of California, have invented a certain new and useful Rotary Drill-Bit; and I do hereby declarethe following to be a full, clear, and exact descrip-, 'tion of the invention, such as Wlll enable others skilled in the art to which it appertains to make and-use the same.

This invention relates to drill bits, more particularly: to such as are actuated by rotation thereof; and it may be said to .con-' sist in the novel construction, arrangement and combination of'the parts of the bit, as will appear from the description and claims hereinafter.

Qbjects of the invention are to provide an improved drill bit which is durable in use, effective in action on hard rock, economical as -to the cost of machine work thereonin manufacture, and the construction of which permits of the parts thereof being quickly assembled, and of such parts as are subject to wear being easily replaced when necessary.

Other objects and the advantages of the invention will be apparent to those skilled .inthe art from a consideration of the following description of one form of construc-- tion in .which the invention may be 'em-' bodied, takenin connection with the accom- T end of a member of the mechanism (not shown) for rotating the bit. The lower end tapered, threaded socket t in the top thereof,

whereby it may be connected to the screw of the shank has removably mounted thereon a hard steel head 5, preferably by mea'nsof the upper portion 6 of the head being, formed and adapted 'to screw into the threaded soeketfl in the lower portion of the shank. The portion 8 of the head .5 contigu'ous 'toportion 6 thereof may be made to be of "slightly increased diameter .as com-- pared with the lower end "portion of shank 2, and thereby is provided the' annular shoulder 9 on which the'lower end of the shank may rest whenthe head is mounted on the shank. At the lower end of the head" grooves 12, each made converging inwardly,, are provided in the lower end portion of the The construction w ereby.

liead 5 and the cutters are each made to have the upper portion 13 thereof in the form of a tenon adapted to fit in the grooves to hold the cutters to-the head, as will be understood. .The inner ends 14 of the upper portions 13 of the cutters preferably terminate at the central passageway 15 in the head, which passageway registers with the passageway 16 in the shank the passageways being adapted to carry water to facilitate drilling operations. I

. To retain the cutter 10 in place on the portions 22 of the outer end faces of the cut- ,ters. It will be seen that with the construction just described the sleeve .17 may be turned farther down to have the cutters fit in the grooves 12 in case of wear causing them to work loose therein; and any of the 'head, a sleeve 17, having its upper portion cutters can be readily replaced when desired by first turning the sleeve to move it upwardly, and after substituting the new cutters turning the sleeve to move it downwardly to place it over the tapered upper portion of the outer ends of the cutters;

As shown,- the lowerend part of the head preferably has a portion or head 23 extend;

- ed to be substantially'in line with the exterior surface 24, of thesleeve 17, and the outer -faces 25 of the cuttingportion of the cutter preferably taper downwardly and; outwardly .to have the outerend of the cutting edge terior surface 24 of the sleeve.

While. one form of construction in which the invention may be embodied has been illustrated and described, there are many 26' of the cutters extended beyond the exchanges and modifications that will occur to those skilled the art, and'the right is ion l lo

therefore reserved'to all such changes andmodifications as do 'not depart from the spirit and scope of the invention.

I claim: 0 p

1, In a rock drill, the combination of a head formed with a' circular cross section and provided with a central longitudinal bore, one end of the headbeingconstructed for engagement with a stock while the opposite endis provided with a series of inwardly converging radially disposed dove tail recesses extending from the central bore to the periphery of the head, a series of cutters'provided with dove-tail tenons adapted to be received within the before mentioned dove tail recesses, the inner ends of the tenons being substantially flush with the walls of the bore through thehead while the outer ends of the tenons project slightly beyond the head, and a sleeve threaded upon the exterior of the head, one edge of the sleeve being designed to project over the outer ends of the-tenons and being inclined so as to force the tenons inwardly and cause them to be securely wedged in the dove-tail recesses.

'2. Ina rock drill, the combination of a. headhaving a circular cross section and providedwith a central longitudinal bore, one end of'said head being surroundedby a bead and provided with a series of inwardly converging radially disposed dove-tail recesses extending from the bore toward the exterior of the head'and having a-unifor'mdepth, I

tenons adapted tobe wedged within the said recesses, the inner ends of the tenons being substantially flush with the walls of the.

inwardly toward the ce nterof the lieadand cause them to be wedged within the dovetail recesses, the working edges of the cutters extending radially beyond the sleeve.

In testimony whereof, I have signed my name to thisspecification in the presence a series of cutters provided with dove-tail of two subscribing witnesses at Los A-nv geles, county of Los Angeles, State of Caliornia, this 26th day of August A. D. 1910.

WM. KAMMERER.

,Witnessesr DAVE F. SMITH, A. -H. LI-DDERS. 

